feees



(No Model.)

0. A. PREES.

ARTIFICIAL LEG.

No. 368,580. Patented Aug. 2.3, 1887.

FIEJ

WITNEEIEEEI, I INVENTUR N, PETERS Pholo-Ulhogr-aphur. Wmhmglan. D C.

UNITED STATES PATENT OFFICE.

OHANCY A. FREES, on NEW YORK, N. v.

ARTIFICIAL LEG.

SPECIPIGATION forming part of Letters Patent N 0. 368,580, dated August23, 1887.

Application filed April 2, 1887.

Serial No. 233,537. (No model.)

To all whom, it may concern:

Be it known that I, CHANCY ADELMER Burns, a citizen of the UnitedStates, residing at New York, in the county and State of New jointsthereof. It also relates to the diaphragm tificial leg that supports thestump.

The invention consists in the various features of improvementhereinafter more fully pointed out in the claims.

In the accompanying drawings, Figure 1 is a longitudinal central sectionthrough an arprovided with my improvement. Fig. 2 is a top view of thefoot. Fig. 3 is a bottom View of the leg. Figs. 4, 5, and 6 arerespectively top, edge, and bottom views of the plate 0. Figs. 7, 8, and9 are detail views of the several parts of the knee-joint.

The letter A represents the artificial leg made of the usual form andentering a socket in the foot B.

a is a jointed pin or a cord secured to the leg and passing through aperforation of the 1 foot, to whichit is held by a nut, b, or otherwise.This pin or cord serves to connect the parts. The joint proper, uponwhich the leg may rock backward and forward and also laterally, consistsof a cross-shaped plate, 0, which is perforated centrally to permit thepassage of pin a. By passing the pin directly through aperforation insuch plate the construction of theparts is greatly simplified and theirworking is improved. The two shorter or transverse arms d of the plate 0are bulged on top, resting within sockets of the leg, and constituting afulcrum upon which the leg may rock backward and forward. The twolongitudinal arms 6 e are bulged at their bottom, resting within socketsof the foot, and constituting a fulcrum upon which the leg or foot maywork laterally. The forward arm, e, is preferably more or lessball-shaped, as shown, and may be connected by an elastic string, f, toa hook, g, to which there is also connected the heel-tendon h.

In order to properly limit the movement of the leg upon and the footbeneath the plate 0, I employ bulged cushions i j, attached, re

spectively, to the leg and foot and fitting into the concavities of thearms 6 (Z.

k is the side rod projecting from the upper end of the leg, and providedwith a conical head, Z, which is made with a screw-threaded centralperforation. This head is embraced by a tapering ring, m, attached tothe thighbar m. A headed screw, or, entering head Z,

will secure the parts to each other, and by adjusting the screw thejoint may be tightened or loosened. The advantage of this construc tion,and particularly of the perforated coni cal head, is that the screw hasa large surface with which to engage, and thus the joint is not apt towear out.

0 is a ring fitted into the upper part of the leg and made of concaveform in cross-section.

This ring is entirely inclosed within the leg,

as shown. Upon this ring and around its cireumferehce there is placedthe buckskin diaphragm p, which bears the end of the stump. Strings q,surrounding the ringo and the edge of the diaphragm, hold the latter inplace. These strings are placed in the annular space between leg andring. It will be seen that by making the ring of concave form I obtainroom for the string. The ring may be secured to the leg by screws orotherwise, and it may be attached higher or lower to conform to thelength of the stump.

I am aware that it is not new plate between the leg and foot portion,the said plate having lateral and longitudinal bearing arms; but I amnot aware that any one has heretofore provided a plate or casting withlateral and longitudinal branches having a central vertical aperture forthe passage of the connecting cord or bolt, and I attach importance tothe employment of a casting or plate of this character, and .to the factthat the to arrange a said branches have bulged bearing-surfaces.

and leg sections,

of a cruciform plate or casting having a vertical aperture for thepassage of the conupon the inserted cushions, substantially asmeeting-cord, substantially as specified. specified. 2. Thecombination,with the foot and leg 3. The combination of leg A with the consections,of a cruciform plate or casting having cave ring 0, placed Within theleg, diaphragm 5 a central vertical aperture for the passage of p, andstring q, placed in the annular space be- 15 the connecting-cord, thelateral branches of tween ring and leg, substantially as specified.

thesaidcastinghavingtheiruppersidesbulged O. A. FREES. and their undersides recessed, and the longi- Witnesses: tudinal branches having theirunder sides F. V. BRIESEN,

IO bulged and their upper sides recessed to bear HENRY E. ROEDER.

